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NASA's Mars Curiosity rover wiggled its wheels Tuesday and is ready to make its first -- if brief -- test drive on Wednesday.

As part of a series of major tests that have been running over the past several days, the robotic rover on Tuesday tested its wheels to make sure it's ready for its first drive.

All six of Curiosity's wheels move and the four corner wheels all are able to steer, according to Michael Watkins, a mission systems manager at NASA's Jet Propulsion Laboratory. Speaking at a press conference Tuesday, Watkins said with this successful "wheel wiggle" test complete, NASA is ready for the rover's first drive.

On Tuesday night, NASA engineers will send the rover commands to make its first moves across the Martian surface on Wednesday.

It won't be a long trek. The rover is expected to drive forward about 3 meters, turn around and drive back nearly as far.

"The Curiosity rover and the ops team continue to hit home runs here," Watkins said. "We've gotten through all of the tests successfully and on schedule... We have aggressive plans this week."

Today's wheel wiggle is one in a series of critical tests for Curiosity, which landed on Mars just over two weeks ago.

On Sunday, the rover used its laser for the first time. It zapped a fist-sized rock with 30 pulses of its million-watt laser beam and then captured the light from the resulting plasma to analyze the rock's makeup.

On Monday, NASA reported that Curiosity unstowed its 7-foot robotic arm and checked its joints and motors by extending and flexing it before stowing it again.

Wednesday's test drive will be the next critical step in testing the rover to make sure it's ready to take its first trek. That first trip is expected to take Curiosity to Glenelg, a spot that NASA scientists are eager to examine because it's at the intersection of three different kinds of terrain.

NASA expects that it will take Curiosity three to four weeks to reach Glenelg.

NASA also reported that scientists discovered a scientific instrument onboard Curiosity that is not working correctly. It's the first report of an instrument that is not working normally.

One of Curiosity's weather-sensing instruments -- its Rover Environmental Monitoring Station (REMS) - is damaged. The instrument, which sits on the rover's 7-foot-tall mast, isn't sending back good data. Though NASA scientists say they may never know what happened, they suspect it was damaged by rocks and debris kicked up by Curiosity's landing engines.

The damaged instrument means NASA won't be able to get as complete a picture of Mars' weather as scientists had hoped, since the rover will have difficulty sensing wind speed and direction.

This animation depicts movements of the robotic arm of NASA's Mars rover Curiosity as commanded for Aug. 20, the first time the arm was used on Mars. The animation is derived from visualization software that rover planners use in developing the commands sent to the rover. (Image credit: NASA/JPL-Caltech)